How to flush coolant properly.
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From: Rochester Hills Michigan
How to flush coolant properly. Like it says, I flushed my coolant a couple days ago. I put a hose in the radiator, opened the bottom plug, turned on the car and turned on the hose. IT flushed all the old dexcool out of my system. I let it run for about 30 with the hose in the radiator. Then i stuck the hose in the resevoir, flushed all that out. Then i added a gallon of dexcool/distill 50 50 mix to the radiator. Started the car up and let it run. Made sure there was no air in the radiator by shakin it and what not till no bubbles came out. I put the rest of the dexcool in the resevoir. Are there any ill effects from too much coolant? I know its spraying out of my resevoir into my engine bay because it was too full. Did I do this correctly? Are their any bleedervalves i can open to make sure I got all the air out? somebody help 
hmmm, hard to explain the bleading procedure that I use, but I'll try.
1. There's the little tube that connects to the radiator right below the cap and the reservior tube, take that off and let it drain into a bottle or bowl. Plug the radiator end. Also either put a kink in the reservior tube or remove and plug.
2. Fill radiator with 50/50 mix and blow into radiator (careful, don't swollow any coolant) to pressurize system.
3. Keep refilling and pressurizing the radiator/system until you get a steady stream of coolant running out of the above mentioned tube that was directed into a bottle. This would eliminate the air pockets in the block and heads.
4. put the lines back on (making sure you don't get much air in the tubes) and top up the radiator.
As for the bottle, keeping it filled to the level on the dipstick is sufficient. Don't overfill, makes a mess like yours. lol
Hope this info helps. Anyone else, feel free to chime in with comments!
1. There's the little tube that connects to the radiator right below the cap and the reservior tube, take that off and let it drain into a bottle or bowl. Plug the radiator end. Also either put a kink in the reservior tube or remove and plug.
2. Fill radiator with 50/50 mix and blow into radiator (careful, don't swollow any coolant) to pressurize system.
3. Keep refilling and pressurizing the radiator/system until you get a steady stream of coolant running out of the above mentioned tube that was directed into a bottle. This would eliminate the air pockets in the block and heads.
4. put the lines back on (making sure you don't get much air in the tubes) and top up the radiator.
As for the bottle, keeping it filled to the level on the dipstick is sufficient. Don't overfill, makes a mess like yours. lol
Hope this info helps. Anyone else, feel free to chime in with comments!
On The Tree
Joined: Jan 2004
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Ummmm....if you flush the system with a hose didn't you just contaminate it with the tap water? We all know that Dex-cool and tap water don't get along, thus the need to mix it with distilled water. Surely you won't be able to get all the tap water out of the system after doing something like that. I wonder what a GM shop manual recommends as the proper procedure for flushing the system. Are there any GM techs that can chime in on this?
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TECH Enthusiast
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From: Rochester Hills Michigan
Buddy is a ASE mechanic, he said it would be ok. Flush radiator, drain it all out, then add dexcool.. just makin sure i got the air out, the car is runnin fine.
